Mr Kasshun was attacked by a gang of youths and died in hospital two days later. The following year Mr Hallam, then 17, was one of two people convicted of the murder.

Now 24, Mr Hallam has always maintained his innocence.

Friends and relatives convinced of his innocence joined in a pre-appeal vigil on Tuesday night. Crowds of people turned out at St John’s Church, in Hoxton, despite the pouring rain and released hundreds of yellow balloons into the night sky to symbolise their hopes for his release.

Earlier today his barrister referred to “a case that was crying out for judicial intervention.”

Lady Justice Hallett DBE, who sat alongside Mr Justice Spencer and Mr Justice Openshaw, asked the defence to focus on what she called the “three planks of the crown’s case”.

These were the testimony of a male and female witness and the question of Mr Hallam’s “false” alibi.

The court heard Mr Blaxland QC, for Mr Hallam, question how the female witness had changed her evidence. He said: “There was nothing in her original statement – no reference at all to Sam Hallam. The police said there was nothing to suggest she had seen somebody she recognised but could not name. There was no Mr X.”

The witness later claimed she had recognised Mr Hallam, and he said police had asked her leading questions to make the identification sound more positive in court.

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